For every day use, my system run the rt-sources, which imply no cgroups. The system use openrc with no *kit (and no systemd of course). That on an almost 4 years old asus laptop with 2 cores amd cpu. It work very well. As such a rt kernel can exhibit random failures with gcc (see Compilation failure metabug), I reboot the machine with a gentoo-sources kernel when using emerge.

With the gentoo-sources (today 4.4.39), the cgroup config follow the explanation on the JACK wiki how to get real-time with the cgroup:

Code:

# cat .config |grep CG
CONFIG_CGROUPS=y
# CONFIG_CGROUP_DEBUG is not set
# CONFIG_CGROUP_FREEZER is not set
# CONFIG_CGROUP_PIDS is not set
# CONFIG_CGROUP_DEVICE is not set
# CONFIG_CGROUP_CPUACCT is not set
# CONFIG_MEMCG is not set
# CONFIG_CGROUP_HUGETLB is not set
# CONFIG_CGROUP_PERF is not set
CONFIG_CGROUP_SCHED=y
# CONFIG_BLK_CGROUP is not set
# CONFIG_NET_CLS_CGROUP is not set
# CONFIG_CGROUP_NET_PRIO is not set
# CONFIG_CGROUP_NET_CLASSID is not set
# CONFIG_TCG_TPM is not set

Also in /etc/rc.conf, I have 'rc_controller_cgroup="NO"', otherwise rc pollute the rt cgroup with things I just don't want in it. Even with that option, I get an openrc hierarchy in /sys/fs:

Code:

# ls /sys/fs/cgroup
cpu openrc

I was very surprised of the cpu usage of cgrulesengd (launched by /etc/init.d/cgred). When merging, that is on a highly loaded system, cgrulesengd is constantly between 0.5 and 2.5 % cpu, which seam already a very high cpu usage for a system daemon. But worst, with a very quite system (with just X, fvwm, jackdbus and a console), cgrulesengd goes up to more than 10% cpu usage.

That imply it look to me that cgrulesengd have a very serious issue with its cpu usage. So, what is the problem: cgrulesengd?, my config?, something else?_________________[[[ To any NSA and FBI agents reading that text: please consider ]]]
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